Halak, 27, has appeared in five games this season posting a 3-0-0 record including a 2.10 goals-against average and an .889 save percentage, and is tied for the NHL lead with two shutouts. He had been out with a groin injury.
The Blues are 0-3-1 since starting the season with six wins in their first seven games.
The team also assigned goaltender Jake Allen to their American Hockey League (AHL) affiliate, Peoria Rivermen.
There's no discouragement in that room. There's no issues there at all to be honest with you. It's more about, 'Hey, it's opportunities for players.' And if we become that bad of a team because of one player, it's not a real good sign for our hockey club. So this is part of sports. It's part of hockey.
— Bruins coach Claude Julien on the loss of Zdeno Chara to injury